Naevus Flammeus (Port Wine Stain)

Naevus flammeus, also called a port wine stain, is a permanent birthmark that appears as a pink or red patch on a newborn’s skin. Named because it looks like wine has been spilled on the skin, this harmless mark is present in about 3 out of every 1,000 babies and grows with the child throughout life.

port-wine stain, nevus flammeus, port wine stain, PWS

Table of contents

• What is Naevus Flammeus?
• What Causes Port Wine Stains?
• How Common Are Port Wine Stains?
• What Does a Port Wine Stain Look Like?
• How Are Port Wine Stains Diagnosed?
• Associated Health Conditions
• Treatment Options
• What to Expect Over Time
• Emotional and Social Considerations

What is Naevus Flammeus?

Naevus flammeus is a type of birthmark that shows up at birth as a patch of pink or red skin on a newborn. This mark is not a sign of cancer or abnormal cell growth. Instead, it is caused by a problem with small blood vessels under the skin called capillaries, which are tiny tubes that carry blood through your body^[1].

The birthmark appears because these capillaries did not form properly. They become stretched out or dilated, which means they are more open than normal. This allows more blood to collect in them, giving the skin its distinctive pink, red, or purple color^[2].

This skin condition can appear anywhere on the body and lasts throughout a person’s life. The mark is well-defined, meaning it has clear borders where it starts and stops. It is usually flat and smooth when a child is born^[1].

Port wine stains need to be distinguished from another similar birthmark called a nevus simplex or salmon patch. Salmon patches usually appear along the center of the body and fade away over time, while port wine stains are permanent and do not disappear on their own^[1].

What Causes Port Wine Stains?

The exact cause of port wine stains is not completely understood. Scientists know that these birthmarks result from abnormally formed capillaries under the skin, but they are not certain what causes the capillaries to develop this way^[2].

Most cases happen by chance, which doctors call sporadic. However, some cases run in families, suggesting that genetics may play a role^[1].

Research has identified specific genetic changes that contribute to port wine stains. A somatic mutation, which means a genetic change that occurs after conception rather than being inherited, in a gene called GNAQ has been found in many cases of isolated port wine stains. This gene is located on chromosome 9. The same mutation has also been found in people with a condition called Sturge-Weber syndrome^[1][3].

Other genetic mutations have been identified in different syndromes that include port wine stains. These include mutations in genes called RASA1 and EPHB4, as well as changes in genes like PIK3CA, AKT1, and GNA11^[1][4].

Some evidence suggests that problems with the nervous system may also play a role. Studies have shown that skin with port wine stains has fewer nerve fibers around the blood vessels. These nerves normally help keep blood vessels narrow, so having fewer of them might allow the vessels to stay dilated^[7].

It is important to know that port wine stains cannot be prevented. They are not caused by anything a mother did or did not do during pregnancy^[5][10].

How Common Are Port Wine Stains?

Port wine stains are a relatively common type of vascular birthmark. They affect approximately 3 out of every 1,000 newborn babies, which is the same as 0.3% to 0.5% of all births^[2][4].

These birthmarks affect babies of all backgrounds equally. There is no difference in how often they occur based on a baby’s sex, race, or ethnicity^[2][4].

What Does a Port Wine Stain Look Like?

Port wine stains are pink, red, or purplish patches on the skin. The name comes from their appearance, as they look like someone has spilled or splashed dark red wine on the skin^[2][5].

These birthmarks can appear anywhere on the body. However, they most commonly occur on the face, neck, and scalp. Studies show that 70% to 90% of port wine stains are found on the head and neck. They can also appear on the arms, legs, trunk, or even on mucous membranes inside the body^[1][4].

Port wine stains can vary greatly in size and shape. They may be small or cover large areas of skin. They can be single or multiple, and may affect one or both sides of the body. Most often, they appear on just one side and do not cross the midline of the body^[1][4].

In young children, port wine stains are usually smooth and flat. The color often starts out lighter, appearing pink or pale red at birth^[2][5].

As a child grows, the birthmark grows too, but it stays in the same proportion to the body. Over time, the appearance changes. Port wine stains tend to become darker, often turning a deeper red, reddish-purple, or dark red color. They may also become thicker and develop a bumpy texture that can feel like pebbles under the skin. These changes typically occur during adulthood^[2][5][6].

The skin of a port wine stain may bleed more easily than normal skin when it is scratched or injured, and this bleeding can be difficult to control^[2].

How Are Port Wine Stains Diagnosed?

Doctors can usually diagnose a port wine stain simply by looking at the child’s skin. The distinctive appearance of the birthmark makes it easy to identify in most cases^[2][5].

Port wine stains are typically diagnosed at birth or shortly afterward. When examining a newborn with a port wine stain, healthcare providers will ask about family history to understand if similar birthmarks run in the family^[2].

In most cases, port wine stains are just a cosmetic concern, affecting only how the skin looks. However, doctors will carefully check for signs that the birthmark might be associated with other health conditions^[2].

If the healthcare provider has concerns about the location of the birthmark or notices other symptoms, they may order additional tests. These tests help rule out other medical problems and can include^[2][5]:

• Eye tests to measure pressure inside the eye, which checks for glaucoma, a condition that can damage vision
• Imaging tests such as X-rays, CT scans, or MRI scans to look at structures inside the body
• Skin biopsy, where a small sample of skin is removed and examined under a microscope

In unusual cases, particularly when there is doubt about the diagnosis, a skin biopsy may be performed to confirm that the mark is indeed a port wine stain^[3].

Associated Health Conditions

Port wine stains are usually harmless birthmarks that do not cause any medical problems or pain. For most children, they are simply part of who they are and only affect appearance^[2][5].

However, in rare cases, port wine stains can be a sign of other medical conditions. When they are part of a larger health problem, doctors call this a syndrome^[1].

Sturge-Weber Syndrome

Port wine stains on the forehead or around the eyes may be linked to a rare condition called Sturge-Weber syndrome. In this syndrome, similar abnormal blood vessels appear not only in the skin but also on the surface of the brain and in the tissues covering it. This affects blood flow to the brain and can cause serious complications^[2][5][6].

Children with Sturge-Weber syndrome may experience neurological problems such as seizures, developmental delays, and learning disabilities. They may also develop eye problems including glaucoma^[5][6].

When a port wine stain affects the area supplied by the trigeminal nerve on the face (particularly the forehead and upper eyelid), doctors will monitor the child carefully for signs of Sturge-Weber syndrome^[6].

Klippel-Trenaunay Syndrome

Port wine stains on the arms or legs may be associated with Klippel-Trenaunay syndrome. This rare genetic condition causes abnormal development of blood vessels, bones, and soft tissues in the affected limb. The limb may grow longer or larger than the other one^[2][3].

Eye Problems

Port wine stains located on or near the eyelids can increase the risk of developing glaucoma. Glaucoma is a condition where increased pressure inside the eye can damage the optic nerve and lead to vision loss or blindness if not treated^[2][5].

If a child has a port wine stain near the eye, an eye specialist should examine them to check for any problems^[5].

Treatment Options

Port wine stains that are not associated with other medical problems do not require medical treatment from a health perspective. They are harmless and cause no physical discomfort. However, many people choose to have treatment because of concerns about appearance, especially when the birthmark is large or located on the face^[2][6].

The main treatment for port wine stains is laser therapy. This treatment uses special light to target and destroy the abnormal blood vessels that cause the birthmark^[2][5].

Laser Treatment

The most commonly used laser for treating port wine stains is called a pulsed dye laser. This type of laser produces excellent results in many cases. It works by using targeted heat and light to damage or destroy the blood vessels causing the stain^[3][6][15].

Laser treatment works best when started early in life. Treating the birthmark when a child is still an infant or very young gives the best outcomes. This is because the blood vessels and the stain are both smaller, the stain is lighter in color, and young skin responds better to treatment^[6][15].

Most people need multiple treatment sessions. Studies show that after one to three treatments, more than 25% of the redness is typically reduced. Up to 10 treatments may be necessary for significant improvement^[3].

It is important to understand that laser treatment may not completely remove the port wine stain. The treatment can significantly fade the birthmark and make it much less noticeable, but complete elimination is not always possible, especially with older or deeply rooted stains^[3][15].

After laser treatment, some side effects may occur. These can include pain, crusting, and blistering in the treated area during the first two weeks. Some people may experience changes in skin color, and this is more common in people with darker skin. However, serious complications are rare^[3].

Other Treatment Options

Besides laser therapy, there are other ways to manage port wine stains^[6]:

• Special cosmetic makeup can be used to hide the birthmark. These are opaque creams prepared to match the person’s skin color
• If the port wine stain develops bumpy growths later in life, these can sometimes be removed surgically

In the past, other treatments such as freezing, radiation, and tattooing were tried, but these are no longer commonly used because laser therapy is more effective and safer^[3].

What to Expect Over Time

Port wine stains are permanent birthmarks that do not go away on their own without treatment^[2][5].

Over time, untreated port wine stains usually get worse. They typically become darker in color and thicker in texture. What starts as a flat, smooth, pink patch in infancy often becomes a raised, bumpy, dark purple or red mark in adulthood^[2][6].

As the birthmark ages and thickens, it may develop small lumps or nodules. The surface may become pebbled or rough. Some port wine stains can eventually bleed more easily when injured^[2][3].

The birthmark grows in proportion with the child. As the child gets bigger, the stain gets bigger too, but it maintains the same relative size compared to the body^[2][5].

Occasionally, the underlying tissues beneath a port wine stain may also grow larger. Fat, muscle, and even bone can become thicker in the area of the birthmark. This is most common when the port wine stain is on the face^[4].

The good news is that treatment can prevent or reduce these changes. When laser therapy is started early and performed regularly, it can help keep the birthmark lighter, flatter, and less noticeable throughout life^[6][15].

Emotional and Social Considerations

While port wine stains are physically harmless in most cases, they can have a significant impact on a person’s emotional well-being and social life^[2].

Some port wine stains are barely noticeable, especially when they are small or located on parts of the body that are usually covered by clothing. However, large birthmarks on visible areas like the face can become a source of significant distress^[5].

Children with prominent port wine stains may experience teasing or bullying from peers. This can be especially difficult during the preteen and teenage years, when young people are often more focused on fitting in and looking like their peers^[5].

The visible difference caused by a port wine stain can affect a child’s self-esteem and confidence. Some children may become self-conscious about their appearance, which can impact their willingness to participate in social activities^[2][5].

For many families, these social and emotional concerns are an important reason to consider treatment. Even though the birthmark itself is not medically dangerous, improving its appearance through laser therapy can help a child feel more comfortable and confident^[5].

Parents and caregivers can help children with port wine stains by providing emotional support, addressing their concerns openly, and connecting with support groups where families dealing with similar challenges can share experiences and advice.